Along with the development of social economy and the improvement of living standards, more demands are put forward on living environment. However, in real life, it is usually difficult to understand an indoor environment in a clear and detailed manner, so it is impossible to take measures to improve the indoor environment in time. Instead, the indoor environment may be improved by opening a window or starting such indoor devices as humidifier, air regeneration device and air conditioner for ventilation and temperature adjustment, only in the case that a person does not feel well.